tapping top end of engine. no oil pressure showing. on 1992 Ford E-150

the truck had oil leaks from hell. i replaced the timing cover and oil pan gaskets. while doing so i saw that the timing chain was tight on the right side, with no flex and the left side of the chain was loose, with almost an inch flex. after putting the engine together, the passenger side was making alot of noise. and the oil pressure gauge wasn't showing anything now. did the chain slip and not letting the oil pump work right? HELP HELP!! what do i need to fix?

With that type of chain looseness it should have been replaced while you were in there. It is not causing the oil pressure problem. Maybe you got some debris fallen into the oil pan? Did you have to remove the oil pickup when removed oil pan? If had no problems like this before your work then I would say you may have to back track and disassemble to find problem. Gasket sealer may have been too much and oozed out when tightened cover and pan and got into the oil pickup. Sounds stupid but you did refill with oil, right???